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Conventions In Corona

Names or Identifiers in Lua can be any string of letters, digits, and underscores, not beginning with a digit. The following keywords are reserved and cannot be used as names:
          and     break        do          else     elseif      end        false
          for      function      if             in         local       nil          not
          or       repeat        return     then     true        until        while

The following strings denote other tokens: 

            +        -         *          /         %         ^        #
           ==      ~=       <=      >=       <          >       =
           (           )        {           }         [           ]
            ;           :        ,           .         ..          ...

Lua is a case-sensitive language.
Global variables:
Identifiers starting with an underscore followed by uppercase letters (such as _Global) are reserved for internal global variables used by Lua. 


A comment starts with a double hyphen (--) anywhere outside a string. 
You can comment out a full block of code by surrounding it with   --[[..........]].
To uncomment the same block, simply add another hyphen to the first enclosure, as in
    --single line commented out
    --[[ entire block commented out
         print( 10 )
         print( 15 )
A numerical constant can be written with an optional decimal part and an optional  decimal exponent. Lua also accepts integer hexadecimal constants, by prefixing them  with 0x. Examples of valid numerical constants are:
 3    3.0    3.1416    314.16e-2    0.31416E1    0xff    0x56 5    3.0    5.14    2314.16e-2    0.3456E1    0xff    0x56


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